STR:

1. Latest Nightly 115.0a1 (2023-05-30), Ubuntu 23.04 (R600).

    gfx.webrender.all = true  
    media.ffmpeg.vaapi.enabled = true
    media.hardware-video-decoding.force-enabled = true

2. Play a H264 mp4 file.
3. Visit about:support.

Hardware decoding stopped working for H264 videos with these settings.

The blocklist FEATURE_HARDWARE_VIDEO_DECODING_NO_R600 is overridden but H264_HW_DECODE shows as blocklisted FEATURE_FAILURE_VIDEO_DECODING_MISSING.

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=752dc76b26eb54e7dfa875c749e91526496688b6&tochange=66bf60da3f97ba47a416a97db7ba374f4b86d66c

Regressed by Bug 1831038.

:stransky, since you are the author of the regressor, bug 1831038, could you take a look?

For more information, please visit BugBot documentation.

Plase run Firefox on terminal with MOZ_GFX_DEBUG=1 env variable and attach output here.
Thanks.

Output of MOZ_GFX_DEBUG=1 firefox.

https://searchfox.org/mozilla-central/rev/daedd554ae8a2c7f420ad77311134c8c298ba318/widget/gtk/GfxInfo.cpp#1158-1159

if (aFeature == nsIGfxInfo::FEATURE_HARDWARE_VIDEO_DECODING &&
*aStatus == nsIGfxInfo::FEATURE_STATUS_OK) {
GetDataVAAPI();

I assume Feature Status is FEATURE_HARDWARE_VIDEO_DECODING_NO_R600.

Would this work?

if (aFeature == nsIGfxInfo::FEATURE_HARDWARE_VIDEO_DECODING
  && (*aStatus == nsIGfxInfo::FEATURE_STATUS_OK || media_hardware_video_decoding_force_enabled_AtStartup())
) {

I see. Well we should move the VA-API test to gfxPlatform then.

Set release status flags based on info from the regressing bug 1831038

(In reply to Darkspirit from comment #4)

Would this work?

if (aFeature == nsIGfxInfo::FEATURE_HARDWARE_VIDEO_DECODING
  && (*aStatus == nsIGfxInfo::FEATURE_STATUS_OK || media_hardware_video_decoding_force_enabled_AtStartup())
) {

That looks reasonable.

Backed out for causing build bustages in widget/gtk/GfxInfo.cpp

Backout link: https://hg.mozilla.org/integration/autoland/rev/b59d1203e6bdd6f11c4a3f150e0ccd4abf963942

Push with failures

Failure log -> ERROR - /builds/worker/checkouts/gecko/widget/gtk/GfxInfo.cpp:1159:23: error: no member named 'media_hardware_video_decoding_enabled_AtStartup' in namespace 'mozilla::StaticPrefs'

L.E.
Also these xpc failures

try: https://treeherder.mozilla.org/jobs?repo=try&revision=1a4ea508dba372d2d504469a174f529765dbdca0

:stransky any updates on this?
Next week is the final week of Fx115 beta

try: https://treeherder.mozilla.org/jobs?repo=try&revision=d5e6f04da3a922bc54a9d0792d4c79db8fe15ee5

https://hg.mozilla.org/mozilla-central/rev/7a8c23db9c24

Comment on attachment 9339984 [details]
Bug 1836021 [Linux] Probe VA-API devices if HW acceleration is force enabled (beta) r=emilio

Beta/Release Uplift Approval Request

• User impact if declined: VA-API will be disabled for users who enabled it before by pref. That's unfortunate as we're going to ship VA-API by default for all Intel GPU in 115. So users with VA-API explicitly enabled for FF < 115.0 will end up with broken config.
• Is this code covered by automated tests?: No
• Has the fix been verified in Nightly?: No
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Enable VA-API probe when user asks for it (set by pref). It should not add a regression as it keep behavior from 114 line.
• String changes made/needed:
• Is Android affected?: No

Comment on attachment 9339984 [details]
Bug 1836021 [Linux] Probe VA-API devices if HW acceleration is force enabled (beta) r=emilio

Approved for 115.0b8.

https://hg.mozilla.org/releases/mozilla-beta/rev/1fd1675876cf